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PET/ PETE: Polyethylene Terephthalate 1. Thermoplastic polymer in polyester family, with â€Å"C10H8O4† as empirical formula for its monomer. 2. It exists in two forms: fiber (synthetic) and resin. 3. PET is converted into fiber form by permanent press fabric and bottles by blow molding. 4. Recycling Code: #1 5. PET is not biodegradable and its incineration produces harmful gases which have high potency to air pollution. That’s why recycling it for further use. Properties [1] Density 1.38 g/cc (20 â„Æ') Young's Modulus 2800-3100 MPa Tensile Strength 55-75 MPa Elastic Limit 50-100% Glass Transition Temperature 67-81 â„Æ' Table 1: Properties of Poly-Ethylene Terephthalate. 6. Strength and stiffness of PET exists because of the presence of large aromatic rings in the long chains which results in high resistant to deformation too [2]. 7. PET (waste) used as construction materials: Based on available research in the literature, waste PET (mainly bottles) is recycled in four major ways: I. Waste PET bottles depolymerized into unsaturated polyester resin to produce polymer mortar and polymer concrete [3]. Advantages: †¢ Higher compressive and flexural strength than normal Portland cement. †¢ Modified concrete achieves 80% of its ultimate strength within 1 day. Disadvantages: †¢ Properties of modified cement sensitive to temperature. †¢ Cost for producing this modified concrete is high. II. PET Fiber to reinforce concrete [4]. Advantage: †¢ Enhances the ductility of quasi-brittle concrete. †¢ Reduce the cracking by plastic shrinkage. Disadvantage: †¢ Water Repellent and low surface energy of plastic which result in weak mechanical bonding b/w fiber and concrete. †¢ Poor mechanical bond strength causes internal micro-cracks in the interfacial mechanical... ...s Composites, 21(17): 1597–1607, 2002. 16. A. B. Inceoglu and U. Yilmazer. Synthesis and mechanical properties of unsaturated polyester based nanocomposites. Polym. Eng. Sci., 43(3): 661–669, March 2003. 17. M. S. Devi, V. Murugesan, K. Rengaraj, and P. Anand. Utilization of flyash as filler for unsaturated polyester resin. J. Appl. Polymer Sciences, 69(7): 1385–1391, August 1998. 18. A. B. Cherian and E. T. Thachil. Blends of unsaturated polyester resin with functional elastomers. J. Elastomer Plastics, 35(4):367–380, October 2003. 19. Y. Xu, M. L. Li, Y. Guo, and F. J. Lu. Structure and properties of modified unsaturated polyester resin by nano-TiO2. J. Mater. Sci. Technol., 19(6): 578–580, November 2003. 20. E. Kicko-Walczak. New ecological polyester resins with reduced flammability and smoke evolution capacity. J. Appl. Polym. Sci., 74(2):379–382, October 1999.